• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.930-933
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• 2000

In this report experimental ultrasonic machine system has been fabricated and experimental machining has been performed using glass as a workpiece material. As grit size increases, material removal rate(MRR) was observed to be increased at decreased applied tool pressure on the workpiece, however at the higher applied pressure above $2-4\;kg/cm^2$ for smaller grit size, the MRR was not increased. Also better surface roughness was obtained for smaller grit size. Microchipping was observed from the microscopic examination and the pattern is similar to the iso-stress field where cracking is considered to be initiated near the surface.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.5
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• pp.61-66
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• 1997

In this paper we report the fabrication of an InGaAs metal-semiconductor-metal (MSM) photodiode(PD) which an InAlAs barrier enhancement layer that has very low dark current and high speed chracteristics. The detector using Cr/Au schottky metal fingers with 4um spacing on a large active area of 300*300um$^{2}$ offers a low dark current of 38nA at 10V, a low capacitance of 0.8pF, and a high 3-dB bandwidth of 2.4 GHz. To our knowledge, these characteristics are better than any previously published results obtained from large area InGaAs MSM PD's. The RC equivalent model and frequency domain current response model considering transit time were also used to analyze the frequency characteristic of the fabricated device.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1676-1681
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• 2006

We report on Organic Vapor Phase Deposition $(OVPD^{(R)})$ an innovative deposition technology for organic light emitting device (OLED) and organic semiconductor manufacturing. The combination of $OVPD^{(R)}$ with Close Coupled Showerhead (CCS) technology results in manufacturing equipment with vast potential for cost effective manufacturing of OLED displays commercially competitive to LCD. The actual $OVPD^{(R)}$ equipment concept and design is discussed: Computational Fluid Dynamic (CFD) modeling is compared with experimental results proving the excellent controllability of the deposition process. Further other production relevant deposition properties are being reviewed e.g. high deposition rates and high organic material utilization efficiency of the $OVPD^{(R)}$ - Technology. Data from devices made by $OVPD^{(R)}$ show comparable/ superior performance to those fabricated with conventional vacuum thermal evaporation (VTE) techniques. An outlook on further potentials of $OVPD^{(R)}$ with respect to enabling advanced organic device structures is given.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1424-1427
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• 2005

In this paper, we studied on the application of Organic Thin Film Transistors (OTFTs) to the active matrix organic light emitting diodes (AMOLED). We designed organic transistor based pixel circuits for AMOLED. The pixel circuit is consisted of two-transistor, one-capacitor and one-OLED. We report the simulation results of the pixel circuits that OLED current varied as the data line and scan line voltage. Also, we will describe the fabrication process of the Pentacene OTFTs arrays and the organic light emitting diodes. The driving results of the fabricated unit pixels and their 4x4 arrays are also presented.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1432-1435
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• 2006

We report on carbon nano-fibers (CNFs) for applying to epoxy as a highly thermal conductive adhesive. In order to fabricate CNFs, electro-spinning process was performed with polyacrylonitrile (PAN) solutions. The sample was stabilized at the annealing temperature of $360^{\circ}C$, and carbonized from 900 to $1100^{\circ}C$. It is shown that the synthesized CNFs have a good thermal conductivity of several hundred W/m K. LED backlight units (BLUs) fabricated with MPCB using CNF-mixed epoxy give a better heat dissipation and higher performance than normal LED BLUs. On the basis of SEM, XRD, and FTIR, the characteristics of CNFs are described.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.649-652
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• 2003

Organic thin-film transistors were fabricated using pentacene as an active electronic material. Device characteristics are improved with increasing the deposition rate of pentacene. It is observed that the deposition rate influences on the interface properties between pentacene and polystyrene, and the molecular ordering of pentacene film. In this paper, we report the effects of the deposition rate of pentacene film on the device performance.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.484-485
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• 2003

We report on the optimization of the fabrication process of hybrid sol-gel thin film deposition to produce low cost $1 {\times} 16$ splitters for optical communications. We learn that sol-gel film thickness is dependent upon the spinning speeds and viscosity of the sol-gel solutions and refractive index upon the dopant concentrations of Al and Zr in the sol solutions. We could find the optimized physical conditions to achieve the desired thickness of core and cladding layers. We will further carry out the fabrication and measurements of insertion loss, polarization dependent loss (PDL), etc. for the performance of fabricated splitter devices.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.935-936
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• 2003

We report a novel observation of reversible color adjustability in polymer light-emitting diodes (PLED) fabricated with a single material. When we controlled applied bias of PLED, we found that the devices change their emission color. Moreover, this process is reversible. This result exhibits a new possibility of voltage-tunable color PLED.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.978-980
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• 2003

Perylene tetracarboxylic anhydride derivatives have been well-known as an n-type channel material.$^1$ Here, we report perylene-based pyrrolopyrone derivatives as an n-type channel material. 1,8-naphthalene(l) and 1,2-phenylene(2)-based pyrrolopyrone derivatives were synthesized and characterized. Derivatives 1, 2 were soluble only protonic solvents with high acidity such as methane sulfonic acid and trifluoroacetic acid. Thin film transistors were fabricated by vacumn deposition and solution casting and electron mobility of the device were measured.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.159-162
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• 2005

In this paper, we report a novel technique for the manufacture of polymeric bar-coded strips having diverse characteristics such as sensing with biocatalysts using a microfluidic platform and 'on the fly' photopolymerization. This method is a very simple, cost-effective means for mass production, and diverse materials sensitive to hazardous environments such as enzymes, DNA, or antigens are expected to be immobilized stably, as the fabrication process does not need any hazardous environments. On the basis of this technology, we fabricated enzyme-immobilized barcoded strip for multiple bio-analysis.